I'm out of my comfort zone, but here's what I've been able to pick up about mountain bikes here in Bloomington.
650B -- Not just for the wool knicker crowd anymore, 650B is clawing its way up to Ross Perot status in the hearts of MTB product folks who are sick of the 26 v. 29 partisan warfare. Maybe it is the plain-talkin alternative to those kevlar beltway insiders, or maybe it's just a well-financed crackpot idea. Regardless, four manufacturers are tooling up 650B mountain tires, so if tire choice is holding you back, stay tuned.
Disc Powertap -- For mountain guys who wanted to quantify their lack of training, see below. The everpresent Saris randomly raffled off a few of these, and one of the lucky winners was a nice guy named Michael. Michael works for a shop called the Old Spokes Home, asked if this Powertap thing powered a dynamo light, requested a three-speed internal version, and professed a willingness to trade for boxfuls of Sturmey-Archer spares. Here's their homepage pic, for contextual purposes:
Reba 29er -- Apparently new, and somehow novel, I'm told. I nodded politely. The graphics are slated for revision, for those who care.That's all I can muster. With that out of the way, I'll post up some stuff I can actually talk about intelligently pretty soon.